The above round terminal fixation structure is used for example in an on-vehicle electrical junction box (see PTL 1). FIG. 15 is a perspective view showing a main part of an junction box electrical junction box using a conventional round terminal fixation structure. FIG. 16 is a perspective view show the round terminal fixation structure shown in FIG. 15. FIG. 17 is a perspective view showing a state before the round terminal is fixed to the electrical junction box shown in FIG. 15. FIG. 18 is a bottom view showing the electrical junction box shown in FIG. 17. FIG. 19 is an explanatory view showing an operation for fixing the round terminal to a bus bar shown in FIG. 17.
A round terminal fixation structure 301 shown in FIG. 15 is configured to fix a round terminal 3 (also referred to as LA terminal) connected to an end of an electric wire 2 to a bus bar 304 shown in FIGS. 17 to 19 in an overlapping manner with a bolt 5. Further, FIG. 15 shows a main part of an on electrical junction box 310 using the round terminal fixation structure 301.
In FIGS. 15 and 17 to 19, a reference sign 8 denotes a block made of synthetic resin. The bus bar 304, a nut 7 to which the bolt 5 is screwed and a not-shown plurality of components such as a relay and a fuse are attached to this block 8. A portion of the bus bar 304 is exposed at a terminal connection portion 80 of the block 8, and the round terminal 3 is overlapped with this exposed portion. In FIG. 15, an arrow B denotes a rotation direction of the bolt 5 upon screwing with the nut 7.
As shown in FIG. 16 (in FIG. 16, an illustration of the block 8 is omitted), the round terminal 3 includes: a bolt insertion portion 31 provided with a first through-hole 30 through which the bolt 5 is passed; a core wire crimp portion 32 for crimping a core wire 21 of the electric wire 2; and an insulating cover crimp portion 33 for crimping an insulating cover 22 of the electric wire 2.
As shown in FIG. 16, the bus bar 304 includes: a flat plate portion 341 provided with a second through-hole 340 through which the bolt 5 is passed; a rotation restriction piece 342 vertically extending from the flat plate portion 341 to restrict the rotation of the round terminal 3 when tightening the bolt 5, and a plurality of connection portions (not shown) electrically connected to the relay or the fuse.
As shown in FIG. 19, in such round terminal fixation structure 301, the round terminal 3 is inserted into the block 8 and overlapped with the terminal connection portion 80 of the bus bar 304, and the bolt 5 having a washer 6 is inserted into the first through-hole 30, the second through-hole 340 and the nut 7, and then the bolt 5 is rotated in the B direction (see FIG. 15) to be screwed with the nut 7, thereby the round, terminal 3 is fixed to the bus bar 304 and the round terminal 3 is electrically connected to the bus bar 304.